Third-order structure functions for isotropic turbulence with bidirectional energy transfer

We derive and test a new heuristic theory for third-order structure functions that resolves the forcing scale in the scenario of simultaneous spectral energy transfer to both small and large scales, which can occur naturally, for example, in rotating stratified turbulence or magnetohydrodynamical (M...

Full description

Saved in:
Bibliographic Details
Published inJournal of fluid mechanics Vol. 877
Main Authors Xie, Jin-Han, Bühler, Oliver
Format Journal Article
LanguageEnglish
Published Cambridge Cambridge University Press 25.10.2019
Subjects
Energy
Energy transfer
Fluid mechanics
Fourier transforms
Isotropic turbulence
Magnetohydrodynamic turbulence
Theories
Theory
Turbulence
Online AccessGet full text

Cover

More Information
Summary:We derive and test a new heuristic theory for third-order structure functions that resolves the forcing scale in the scenario of simultaneous spectral energy transfer to both small and large scales, which can occur naturally, for example, in rotating stratified turbulence or magnetohydrodynamical (MHD) turbulence. The theory has three parameters – namely the upscale/downscale energy transfer rates and the forcing scale – and it includes the classic inertial-range theories as local limits. When applied to measured data, our global-in-scale theory can deduce the energy transfer rates using the full range of data, therefore it has broader applications compared with the local theories, especially in situations where the data is imperfect. In addition, because of the resolution of forcing scales, the new theory can detect the scales of energy input, which was impossible before. We test our new theory with a two-dimensional simulation of MHD turbulence.
ISSN:0022-1120
1469-7645
DOI:10.1017/jfm.2019.651